Catalyst materials can be provided in a wide variety of forms. High surface area, high selectivity, good reactivity, thermal stability, and ease of handling are some of the many factors which contribute to a good catalyst material. As a practical matter, many catalyst materials are formed on porous support materials to provide increased surface areas. Further, the support materials themselves can also contribute to the catalytic activity of a catalyst. A wide variety of porous support materials are available. Aerogels are one type of support material which provides very high surface areas and extremely low densities. In fact, aerogels are among the lowest density solid materials currently available. As a result, a number of efforts at developing aerogel supported catalyst materials have met with varying degrees of success. Most often the above factors are difficult to consistently and simultaneously satisfy. For example, aerogels generally are very fragile materials which tend to degrade in the presence of water and other solvents. Further, pure ceria aerogels tend to exhibit a significant loss of surface area at elevated temperatures.
In addition, catalyst manufacturing technologies generally produce randomly distributed metal oxides or metals and can suffer from non-selective deposition across the support surface. As a result, catalyst metals tend to associate with one another merely by proximity or by chance. This is especially problematic in multi-metallic catalysts where improved catalytic activity is the result of the combined synergistic effects of each of the constituent co-catalysts. In such products, conventional random deposition techniques result in reduced catalytic activity than might theoretically be expected from the combination of certain co-catalysts.
Therefore, materials and methods which provide improved catalyst support materials which avoid the above difficulties continue to be sought through ongoing research and development.